C 20 3/4 Ton Pickup 2WD V8-350 5.7L VIN L 4-bbl (1983)
ILLUSTRATION
Some C/K Silverado Trucks may exhibit a wind whistling noise in the area of the vent window or the side door glass lower seal when the HVAC blower
is on "high".
This condition is the result of a restriction in air flow from the cab interior to the outside environment. The following procedure will improve the air flow
and eliminate the whistle.
1.
Remove lower door trim panel, exposing louvers at the bottom of the door.
2.
Unscrew the two screws retaining the air valve assembly behind door louvers. Let the valve assembly drop to the bottom of the door.
3.
Use a die grinder with a cut-off wheel to cut the louvers out of the door. Remove any material falling inside the door.
4.
Smooth any rough edges with a file.
5.
Paint exposed metal edges to prevent corrosion.
6.
Reinstall air valve assembly.
